Not yet, but they've only brought a couple old games. If they are planning to do something more substantial, I can see Sony creating their own PlayStation launcher.
Valve shouldn't get any portion of Sony exclusive software. Sony doesn't need them and especially not at 30%.
Good luck to Sony creating a new division with a whole management and bunch of full time employees to create featureless store, only to publish their own games! 30% cut is nothing compared to this!
Also, FYI:
With that in mind, we’ve created new revenue share tiers for games that hit certain revenue levels. Starting from October 1, 2018 (i.e. revenues prior to that date are not included), when a game makes over $10 million on Steam, the revenue share for that application will adjust to 75%/25% on earnings beyond $10M. At $50 million, the revenue share will adjust to 80%/20% on earnings beyond $50M. Revenue includes game packages, DLC, in-game sales, and Community Marketplace game fees. Our hope is this change will reward the positive network effects generated by developers of big games, further aligning their interests with Steam and the community.